2-nitroimidazoles

ABSTRACT

2-Nitroimidazoles substituted in the 1-position with an alkanoic acid, alkanoic acid ester or an N-substituted alkanoic acid amide which are useful as germicides, antiprotozoal agents and as agents for treatment of pathogenic yeast infections.

United States Patent Beaman et al. 1 July 25, 1972 541 Z-NITROIMIDAZOLES [56] References Cited 72 Inventors: Alden Gamaliel Beaman, North Caldwell, UNITED STATES PATENTS Robert Dmhinsky, Pully-l-ausanne, 3,037,909 6/1962 Rogers etal. ..260/309 Switzer and; W am Pa New 3,065,133 11/1962 Tchelitchefi ..260 309 York, NY.

FOREIGN PATENTS 0R APPLICATIONS [73] Assignee: lloflmann-La Roche Inc., Nutley, NJ.

639,371 4/1964 Belgium ..260/309 [22] Filed: Sept. 12, 1969 211 App]. N6.; 857,556 (HER PUBLICATIONS Lanciniet a]. Experientia Vol. 21, page 83 i965). Q1.Q1E9 Related US. Application Data (January 1965) [63] Continuation-impart 6f Ser. NO. 543,066, April 18, 2 2x35 page Rahway 1960' 1966, Pat. No. 3,505,349, which is a continuation-inpart of Ser. No. 447,103, Aprll 9, 1965, abandoned. Primary Examiner Natalie Trousof Attorney-Samuel L. Welt, Jon S. Saxes, Bernard S. Leon, [52] us. Cl. ..260/309, 260/243 R, 260/243 B, William H Epstein and George Gould 260/244 R, 260 247.5 R, 260 250 R, 260 256.4 N,

260/268 0, 260 293.7, 260/295 K, 260/306.8 R, [57] ABSTRACT 260 307 R, 260/307 l-l, 260/348 A 51 1 1m. 01. ..C07'd 49/36 z-Nltmlmldmles Subsmuted m the 11198111911 Wllh an alkano- 58 Field 61 Search ..26o 309 ic acid alkanoic acid ester N-subsmumd alkamic acid amide which are useful as germicides, antiprotozoal agents and as agents for treatment of pathogenic yeast infections.

16 Claims, No Drawings Z-NITROIMIDAZOLES CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of Ser. No. 543,066, filed Apr. 18, 1966 now U.S. Pat. No. 3,505,349 issued Apr. 7, 1970, which is a continuation-impart of Ser. No. 447,103, filed Apr. 9, 1965 now abandoned.

BRIEF SUMMARY OF THE INVENTION This invention relates to novel 2-nitroimiclazoles. More particularly, the invention relates to substituted Z-nitroirnidazoles of the formula l ll B I wherein R and R are each independently hydrogen, lower al kyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aminolower alkyl, halo-lower alkyl, aryl or aralkyl c. secondary amino groups represented by wherein Z represents lower alkylene, aza-lower alkylene, N- lower alkylaza-lower alkylene, oxa-lower alkylene or thialower alkylene so as to form with the nitrogen atom to which they are attached a 5- or 6-membered nitrogen-containing heterocycle; with the proviso that when A is methylene and B is amino, R and R, are both other than hydrogen or lower alk l.

Among the compounds of formula I, there are included compounds of the fonnula:

wherein R R R and R are as above and A is a polymethylene chain of two to six carbon atoms or a polymethylene chain of from two to six carbon atoms wherein one of the hydrogen atoms has been replaced by hydroxy; compounds of the formula:

wherein R and R are as above and R and R are selected from the group consisting of hydroxy-lower alkyl, lower alkoxy-lower alkyl, amino-lower alkyl, halo-lower alkyl, aryl or am]- kyl compounds of the formula:

wherein A, R, R and R are as above; and compounds of the formula:

N o l t-N) wherein A, Z, R and R are as above.

DETAILED DESCRIPTION OF THE INVENTION The term lower alkyl and the lower alkyl portion of the term lower alkoxy as used throughout this specification denotes both straight chain and branched chain saturated hydrocarbons containing one to seven carbon atoms within the chain including, for example, methyl, ethyl, n-propyl, ipropyl, butyl, i-butyl, sec-butyl, t-butyl, pentyl, hexyl and the like. The terms halo and halogen" denote all four halogens, i.e., chlorine, bromine fluorine and iodine. The term halo-lower alkyl represents mono-halo-lower alkyls as well as poly-halo-lower alkyls such as trichloromethyl, trifluoromethyl, 1,2-dichloroethyl and the like. The term aryl" denotes phenyl, substituted phenyl, 5- and 6-membered heterocyclic aromatic groups or 5- and 6- membered heterocyclic aromatic groups wherein one or more of the hydrogens on the ring carbons have been replaced by halogen, lower alkyl, lower alkoxy, trifluoromethyl, nitro or amino. The 5- membered heterocyclic aromatic groups are those heterocyclic groups containing 1-2 hetero atoms which can be either nitrogen, oxygen of sulfur with the proviso that when there are 2 hetero atoms, one of them must be nitrogen. The 6-membered nitrogen-containing heterocyclic aromatic groups are those containing l-2 hetero-nitrogen atoms.

The heterocyclic ary groups can be represented by wherein p= 3-5 q= l-2 p+q= 5-6 Whenp+q=6,YisN;whenp+q=5,YisN,OorSwith the proviso that when q is 2, at least one Y is N.

The term substituted phenyl" denotes phenyl in which one or more of the hydrogens has been replaced by one or more of the functional groups noted below, preferably a substituted phenyl represented by group wherein R, and R. are each independently hydrogen, halogen, lower alkyl, lower alkoxy, trifluoromethyl, nitro or amino. Exemplary aryl groups within the meaning of the term as used in this specification are phenyl, halophenyl, e.g., pchlorophenyl, o-chlorophenyl, o,p-dichlorophenyl, etc., lower alkylphenyl, e.g., p-methylphenyl, etc., lower alkoxyphenyl, nitrophenyl, arninophenyl, p-trifluoromethylphenyl, pyridyl, e.g., J-pyridyl, S-pyridyl, furanyl, thiofuranyl, pyrrolyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, pyrimidyl, e.g., pyrimidyl, pyrazinyl and the like.

The term aralltyl" denotes an alltyl group in which the terminal carbon is substituted by an aryl group as defined above. The aralkyl" groups of this invention are the phenyllower alkyls and substituted phenyl-lower alkyls represented by wherein m is an integer from 1 to 6 and R and R are each independently hydrogen, halogen, lower alkyl, lower alkoxy, trifluoromethyl, nitro or amino and the heterocyclic aromaticlower alkyls represented by oxazolylmethyl, 3-isoxazolylmethyl, pyridyl-lower alkyl, e.g.,

Z-pyridylmethyl, B-pyridylmethyl and 4-pyn'dylmethyl, pyrimidyl-lower. alkyl, e.g., Z-pyrimidylmethyl and 5- pyrimidylmethyl, pyrazinyl-lower alkyl, e. g., 3-pyrazinylmethyl.

The compounds of formula I above wherein B represents the group OR and R is other than hydrogen are prepared by reacting 2-nitroimidazole or the appropriately substituted Z-nitroimidazole with a compound of the formula wherein R is lower alkyl, phenyl-lower alkyl, substituted phenyl-lower alkyl, halo-lower alkyl or amino-lower alkyl and X is a leaving group such as a halogen, tosyl or mesyl,

preferably halogen, especially chloro to form the esters of formula l whereinB'represents the group OR wherein R is other than hydrogen. The acids of formula I, i.e., compounds of formula I wherein B represents hydroxy, are prepared by hydrolyzing a compound of formula I wherein B represents 0-11 and R is other than hydrogen. The hydrolysis can be readily efi'ected by treatment with any suitable aqueous base,

. e.g., an inorganic base such as NaOH or a suitable organic base such as a tertiary amine, e.g.,triethylamine. Compounds wherein B represents the group wherein R and R have the same significance as above or a secondary amine of the formula wherein Z has the same significance as above.-

' Alternatively, the compounds of formula I wherein B represents the group m -N or the group N Z can be prepared by reacting Z-nitroimidazole or the appropriately substituted 2-nitroimidazole with an acetamide of the formula III IV wherein the symbols X, A, R,, R and Z have the same significance as hereinabove. The reaction of nitroimidazole with a compound of formula II or a compound of formulas III or IV 1 is preferably carried out by employing an alkali metal salt of 2- nitroimidazole which can be conveniently prepared by dissolving the 2-nitroimidazole starting material in an alkali metal lower alkoxide, e. g., sodium methoxide, potassium ethoxide,

etc. The reactions are suitably carried out in the presence of an inert organic solvent, e.g., N,N-dimethyl-formamide, N,N- dimethylacetamide, dimethylsulfoxide, lower alkanols, e.g., methanol, ethanol, etc., hydrocarbon solvents, such as toluene, etc., or, if preferred, the reaction, particularly in the case of compounds of formulas Ill and IV, can be carried out in an aqueous medium, or where one of the reactants is a liquid, the reaction can be carried out in the absence of any solvent. The reaction is suitably carried out at an elevated temperature, preferably in the range of about to about The reaction of an ester of formula I with an amine to form the amides of formula I is suitably carried out in the presence of an inert organic solvent, preferably an alcohol, such as methanol, ethanol and the like, although where the amine reactant is a liquid, it can be conveniently employed as solvent. The reaction is conveniently carried out at room temperature though higher or lower temperatures can also be employed. As a practical matter, the reaction is generally carried out at a temperature in the range of about 0 to about 50.

Certain of the compounds of formula I wherein A represents a polymethylene chain of two to six carbon atoms in which one of the hydrogen atoms has been replaced by hydroxy may also be prepared by reacting the 2- nitroimidazole starting material with a compound of the formula wherein B has the same significance as. hereinabove and t is 0 to 4.

The reaction is preferably carried out in the presence of a small amount of a basic catalyst such as K CO or by employing the sodium salt of 2-nitroimidazole starting material in an inert solvent such as an alcohol, for example, ethanol or, if desired, where the formula V reactant is liquid, the reaction can be carried out in an excess of the formula V reactant. The reaction temperature is not critical, though preferably it is carried out at an elevated temperature, i.e., between about room temperature and the reflux temperature of the reaction mixture and more preferably at a temperature between about 60 and 130.

The 2-nitroirnidazole starting materials suitable for use in preparing compounds of formula I can be represented by the formula wherein R and R are each independently hydrogen, halogen or lower alkyl. Compounds of formula VI wherein one or both of R, and R are halogen have not been described in the literature heretofore and, thus, constitute a part of this invention. They are prepared by halogenating 2-nitroimidazole or a 4(5 lower aIkyl-Z-nitroimidazole according to halogenation techniques which are per se known in the art.

Those compounds of formula I which are basic in character can be converted to their acid addition salts by reacting with pharmaceutically acceptable acid addition salts which are prepared from pharmaceutically acceptable acids such as hydrohalic, sulfuric, phosphoric and the like, organic acids, such as acetic, citric, tartaric and the like.

The novel compounds of formula 1 and, where available, their acid addition salts with pharmaceutically acceptable acids are active against bacteria, pathogenic yeasts and protozoa, and are useful as germicides, anti-protozoal agents, and as agents for the treatment of pathogenic yeast infections. More particularly, the compounds of formula I are useful in the treatment of infectious diseases caused by Trichomonas, e.g., T. vaginalis, '1. fetus, etc., Histomonas, e.g., l-I. malegradis, etc., Trypanosomes, e.g., T. crum', T. rhodesiense, T. cougolense, etc. They can be administered orally, parenterally topically or in suppository form, e.g., in combination with the usual pharmaceutical adjuvants. Typical oral internal dosage ranges from about 20 to about 200 mg/kg animal body weight with dosage adjusted to species and individual requirements. Typical formulations are given below.

Tablet Formulation Per Tablet Compound of formula 1 100 mg. Lactose, U.S.P. 202 mg. Corn starch, U.S.P.

Prehydrolyzed food grade corn starch 20 mg. Calcium stearate 8 mg.

Total Weight 410 mg.

4. The mixture was compressed at a tablet weight of 410 mg. using tablet punches having a diameter of approximately three-eighths inch. (Tablets may be either flat or biconvex and may be scored if desired.)

Parenteral Formulation Per cc.

Compound of formula 1 10.2 mg. Propylene glycol 0.4 cc. Benzyl alcohol (benzaldehyde free) 0.015 cc. Ethanol (anhydrous) 0.10 cc. Sodium benzoate 48.8 mg. Benzoic acid 1.2 mg. Water for injection q.s. 1.0 cc.

Procedure (for 10,000 cc.):

1. The 102 gm. of the compound of formula I were dissolved in 150 cc. of benzyl alcohol; 4,000 cc. of propylene glycol and 1,000 cc. of ethanol were added.

20 The 12 gm. of benzoic acid were dissolved in the above. The 488 gm. of sodium 'benzoate dissolved in 3,000 cc. of water for injection were added. The solution was brought up to final volume of 10,000 cc. with water for injection.

3. The solution was filtered through an 02 Selas candle, filled into suitable size ampuls, gassed with N and sealed. It

was then autoclaved at 10 p.s.i. for 30 minutes.

Capsule Formulation Per Capsule Compound of formula I mg. Lactose 83 mg. Corn starch 37 mg. Talc 5 mg.

. Total Weight 225 mg.

Procedure:

1. The compound of formula 1, lactose, and corn starch were mixed in a suitable mixer.

2. The mixture was further blended by passing through a Fitzpatrick Comminuting Machine with a No. 1A screen with knives forward.

3. The blended powder was returned to the mixer, the talc added and blended thoroughly. The mixture was then filled into No. 4 hard shell gelatin capsules on a Parke Davis capsulating machine.

Suppository Formulation Per 1.3 Gm. 'Suppository Compound of formula I 0.100 gm. Refined synthetic cocoa butter, 1,155 gm. coconut derived Carnauba wax 0.045 gm.

Procedure:

1. The cocoa butter and the carnauba wax were melted in a suitable size glass lined container, mixed well and cooled to 45C.

2. The compound of formula I, which had been reduced to a fine powder with no lumps, was added and stirred until completely and uniformly dispersed.

3. The mixture was poured into suppository molds to yield suppositories having an individual weight of 1.3 gms.

4. The suppositories were removed from molds and cooled. They were individually wrapped in wax paper for packaging.

Topical Cream Per 100 Gms. Cream Compound of formula I 10.2 gm. Stearic acid 15.0 gm. Mineral oil light 1.5 gm. Sorbitan monostearate 2.5 gm. Methyl p-hydroxybenzoate 0.08 gm. Propyl p-hydroxybenzoate 0.02 gm. Sorbitol solution NP. 5.00 gm. Polyoxyethylene sorbitan monostearat 1.69 gm. Distilled water 67.5 gm.

Procedure:

1. The stearic acid, mineral oil, sorbitan monostearate and methyl and propyl p-hydroxybenzoates were melted together at approximately 75C. in a suitable size stainless steel, jacketed kettle with agitator.

2. A suspension of the compound of formula 1 in a solution of polyoxyethylene sorbitan inonostearate, sorbitol N.F. and distilled water was added to the melted mixture.

3. The mixture was stirred at 75C. until uniform, and the temperature was gradually reduced with continuous stirring.

4. When the. temperature reached 48C., the. cream was transferred to storage containers.

5. The cream was packaged in wax lined, tin tubes (opal glass jars may also be used).

This invention will be more fully understood from the following examples which are intended to illustrate the invention and are not to be construed as limitative thereof. All temperatures are stated in degrees Centigrade.

EXAMPLE 1 Preparation of 2-nitro- 1 -imidazoleacetic acid ethyl ester To a suspension of 15.1 g. (133 mmoles) of powered sublimed 2-nitroimidazole in 1.00 ml. of N,N-dimethylformamide was added 30.1 ml. of 4.44 N NaOCH in methanol. To the pink solution was added a bit of 2-nitroimidazole until the color just turned yellow again. The solution was stirred and heated to 151 to remove methanol, cooled to 95 and 20.0 ml. (23.2 g., 189 mmoles) of ethylchloroacetate was added. The temperature fell to 90, and then rose to 1 13 over about 3 min. and a precipitate formed. The mixture was stirred and heated at 100-l 15 for 17 min. and the dimethylformarnide was removed in vacuo (0.2 mm, bath 55). The oil was slurried in 125 ml. of absolute ethanol and filtered from the white solid precipitate. The filtrate was evaporated to an oil in vacuo (0.2 mm, bath 44). This oil was shaken with 175 ml. of anhydrous ether (all dissolved except for a slight haze) and 2-3 g. of charcoal was added and the mixture filtered at once rapidly. From the yellow filtrate crystals soon deposited. The mixture was cooled in the freezer for 1.5 hrs. and the crystals collected, washed with ether and dried. The crystals so obtained melted at 47 -49 Recrystallized from 400 ml. of boiling ether, the product was obtained as crystals melting at 48.5"-

EXAMPLE 2 Preparation of N-methyl-Z-nitrol -imidazoleacetarnide Sublimed 2-nitroimidazole (6.95 g., 61.5 mmoles) was slurried in 45 ml. of N,N-dimethylformamide and 13.9 ml. (61.5 mmoles) of 4.44 N NaOCl-l, in methanol was added. Then 7.97 g. (74 mmoles) of N-methylchloroacetamide was added, and the solution was stirred and heated in an open flask. The mixture was faintly cloudy at 80. It was stirred for 15 minutes at l30-153. The mixture was cooled, the NaCl filtered and washed with dimethylformamide, and the filtrate pluswash was evaporated to dryness in vacuo (0.1 mm, 50 bath). The solid which remained was ground with 20 ml. of distilled water, filtered, and washed with two 5 ml. portions of water. The slightly moist solid was recrystallized from .1 ml. of boiling water (3 g. of charcoal) to give pale yellow needles of N- methyl-2-nitrol-imidazoleacetamide, melting point 1 74-175.

Example 3 Sublimed 2-nitroimidazole (17.65 grams, 156 mmoles) was I cooled. The salt was filtered and washed with dimethylformaslurried in 85 ml. of N,N-dimethylformarnide and 35.2 ml. of

4.44 N NaOCH, solution in methanol (156 mmoles) was added. (The solution of 2-nitroimidazole in a deficient amount of NaOCH, in MeOl-l plus dimethylformamide is yellow. Excess NaOCH, gives a pink color. In case'of temporary excess of NaOCl-l, because not all the solid Z-nitroimidazole has dissolved, the pink color becomes yellow again when more of the solid dissolves. The end point is very sharp. One drop of NaOCH, gives a marked change from yellow to pink at the end point). Then 17.5 g. (187 mmoles) of chloroacetamide was added. The solution was stirred and heated in an open flask. The mixture because hazy (precipitation of NaCl) at 105. The mixture was stirred at 150160 for 10 minutes and mide, and the filtrate plus wash was evaporated to dryness in vacuo (0.1 mm. 50 bath). The solid which remained was ground in a mortar with 50 ml. of distilled water, filtered, washed with five 5 ml. portions of water, and dried. The crude material was recrystallized from 200 ml. of boiling distilled water (7 of charcoal) to give pale yellow spear shaped crystals of 2-nitro-1-imidazoleacetamide, melting point 182-183.5.

Example 4 Preparation of N-(2-hydroxyethyD-2-nitro-1-imidazoleacetamide A slurry of 10.0 g. (54 mmoles) of 2-nitro-1imidazole acetic acid methyl ester in 50 ml. of absolute methanol was stirred and 10.0 ml. (10.0 g., 163 mmoles) of 2-aminoethanol (ethanol amine) was added. The solid completely dissolved after about 10 min. and afier an additional 15 min. a new solid began to form. The mixture was allowed to stand at room temperature for 18 hours and was then cooled in the freezer for 7 hrs. The solid was filtered, washed with 2 X 10 ml. absolute MeOl-l and dried. The product was recrystallized from ml. of boiling absolute ethanol to give the product as needles m.p. 162 l63.

EXAMPLE 5 not,

Example 6 Preparation of N-benzyl-Z-nitro- 1 -irnidazoleacetamide A solution of 10.0 g. (54 mmoles) of 2-nitro-1- imidazoleacetic acid methyl ester plus 20 ml. of benzylamine in ml. of absolute methanol was allowed to stand at room temperature overnight with formation of crystals. The mixture was refrigerated several hours and the crystals collected, m.p. 187.5-189.5. The filtrate was concentrated in vacuo, and the solid obtained was recrystallized from 150 ml. of ethyl acetate to give additional product having melting point 187.5489. Recrystallized from 325 ml. of boiling ethanol, the product was obtained as crystals, m.p. 188.5--l90.

x 53. 313 my, e=7600 Example 7 Preparation of N ,N-dimethyl-2-nitro l -irnidazoleacetarnide Fifty milliliters of absolute methanol was cooled in an ice bath and gaseous dimethylamine was bubbled in until the final volume was ml. Then 10 g. (54 mmoles) of 2-nitro-limidazoleacetic acid methyl ester was added and the mixture stirred in a stoppered flask. The solid dissolved, and after about 10-15 min. a new solid began to form. The mixture was allowed to stand at room temperature for 24 hours and then cooled in the freezer for 17 hours. The crystals were collected,

A EtOH max.

Example 8 Preparation of N-ethyl-2-nitrol -imidazoleacetamide 50 milliliters of absolute methanol was cooled in an ice bath and monoethylamine was poured in slowly from a cylinder until the total volume was about 100 ml. Then 10.0 g. (54 mmoles) of 2-nitro-l-imidazoleacetic acid methyl ester was added and the mixture stirred in a stoppered flask. The solid dissolved and after about min. a new solid formed. The mixture was allowed to stand at room temperature for 19 hours and was then placed in the freezer for 4 hours. The crystalline solid was filtered, washed with 10 ml. of methanol and dried. Recrystallized from 75 ml. of boiling absolute ethanol, the product was obtained as crystals melting at l8ll82,

EtOH max.

Example 9 Example 10 Preparation of N-furfuryl-Z-nitrol -imidazoleacetamide A solution of 10.0 g. (54 mmoles) of 2-nitro-limidazoleacetic acid methyl ester plus 20 ml. of furfurylamine in 60 ml. of absolute methanol was allowed to stand at room temperature overnight. The solution was seeded and refrigerated for several hours. The crystals when filtered, washed with cold methanol and dried, melted at l78.5-l 80. Recrystallized from 250 ml. of ethanol, the product was obtained as crystals melting at 179l 80,

X23 312mg, 6=7500.

Example 11 Preparation of N-butyl-Z-nitro-l-imidazoleacetamide A solution of 10.0 g. (54 mmoles) of 2-nitro-limidazoleacetic acid methyl ester plus 20 ml. of n-butylamine in 100 ml. of absolute methanol was allowed to stand at room temperature overnight. The solution was evaporated to dryness in vacuo. The resulting solid was recrystallized from 35 ml. of ethyl acetate (charcoal) to give the product melting at l24-125. (The product softened at 117 and the melting point varied with rate of heating.)

Aggy 312m e=7600.

Example 12 Preparation of 4-[2-( Z-rtitro-l-imidazolyl) acetyl]morpholine A solution of 10.0 g. (54 mmoles) of 2-nitro-limidazoleacetic acid methyl ester in 50 ml. of morpholine was allowed to stand at room temperature for 5 xi days. The solution was evaporated to a yellow oil in vacuo (0.1 mm bath 50). This was dissolved in 25 ml. of warm ethyl acetate and the solution refrigerated to give a crystalline product. Recrystallized from 55 ml. of ethanol, the product was obtained as crystals melting at l 13.5-l 15.

hi1 315mg, e=7500.

Example 13 Preparation of N-[2-( 2-nitrol -imidazolyl)acetyl]piperidine A solution of 10.0 g. (54 mmoles) of 2-nitro-limidazoleacetic acid methyl ester in 50 ml. of piperidine was allowed to stand at room temperature for 2.5 days. The resulting slurry of crystals was concentrated in vacuo to an oily solid. This was dissolved in 30 ml. of hot ethyl acetate and the solution refrigerated to give crystals melting at lO2-l03.5. Recrystallized twice more from ethyl acetate gave the product with melting point unchanged.

Example 14 Example 15 Preparation of N-isobutyl-Z-nitro-l-imidazoleacetamide A solution of 7.00 g. (37.8 moles) of 2-nitro-limidazoleacetic acid methyl ester in 14 ml. of isobutylamine plus 70 ml. methanol was allowed to stand at room temperature for 5 days and evaporated in vacuo to give a yellow solid. Recrystallized once from 65 ml. of absolute ethanol (charcoal) and once from ethyl acetate, the product was obtained as crystals melting at l47.5-148.5.

Example 16 Preparation of N-propyl-2-nitrol -imidazoleacetamide A solution of 7.00 g. (37.8 mmoles) of 2-nitro-limidazoleacetic acid methyl ester and 14 ml. of n-propylamine in 70 ml. of methanol was allowed to stand at room temperature overnight. On cooling, there was obtained crystals melting at l59l60. Recrystallized from 30 ml. of boiling ethanol (charcoal), the product was obtained as crystals melting at l59-l60.5.

Example 17 Preparation of N-( 3-pyridylmethyl)-2-nitro-l-imidazoleacetamide A solution of 7.00 g. v(37.8 mmoles) of 2-nitro-1- imidazoleacetic acid methyl ester and 14 ml. of 3- aminomethylpyridine in 70 ml. of methanol was allowed to stand at room temperature for 4 days and refrigerated to give crystals melting at l89-192. Recrystallized once from 400 ml. of ethanol (charcoal) and once from 230 ml. of water gave the product as crystals melting at 194- 1 955.

X29256, 262 268, 315, mp, e=4600, 4700, 3900, 7600.

Example 18 boiling distilled water, the product was obtained as crystals melting at 162.5163.5.

A222 254, 260, 267, 313 mp,6=5300, 5600, 4600, 7800.

Example 19 Preparation of N ,N-diethyl-Z-nitro-l-imidazoleacetamide A suspension of 10.25 g. (90.5 mmoles) of ground and sieved sublimed 2-nitroimidaz ole in 100ml. of dimethylformamide (DMF) was stirred magnetically and 20.2 ml. of 4.44 N NaOCH, in CH,OH was added. The azomycin dissolved and the solution became pink; addition of a pinch of azomycin gave a yellow solution which was heated to 150 and cooled to 97 and 14.5 ml. (den. 1.10, 16.0 g., 107 mmoles) of N,N- diethylchloroacetamide was added. The temperature fell to 93 and then rose spontaneously to 97 and a precipitate formed. The mixture was heated and stirred at 100 1 20 for 20 minutes. The DMF was evaporated in vacuo (oil pump) and the gum shaken with water to'remove the salt. The oil was then dissolved in acetone and the solution allowed to evaporate in a shallow dish. Crystals formed gradually. After 24 hours, the crystalline product was slurried in 7 ml. 'of 3:1 volzvol 11,0: EtOH, filtered and washed with two times 2.5 ml. of the same solvent mixture and dried. The filtrate plus wash from this material was allowed to evaporate to give a moist solid which was sucked as dry as feasible on a Biichner and slurried on the Biichner in 4 ml. and then 3 ml. of cold 3:1

volzvol 1-1,0:EtOl-l and dried. Recrystallized from 33 ml. of warm 3:1 volzvol H,:EtOH gave the product as crystals melting at 42-44. Upon slow evaporation of the filtrate from the first crop, chunky crystals melting at 6062.5 were ob tained. The [.R. spectra of chloroform solutions of these differently melting crystals were identical, indicating different crystal forms.

A512 313mg, e=8300.

Example 20 Preparation of N-methyl-2-nitrol-imidazolebutyramide To a stirred slurry of 5.10 g. of ground and sieved sublimed 2-nitroimidazole in 50 ml..of dimethylformamide (DMF) was added 9.95 ml. of 4.44 N NaOCH, in CH,OH to give a pink solution. Addition of a pinch of azomycin gave a yellow solution which was heated to 150 and let cool to 109 and with 'stirring 10 ml. (about 10 g. or 73 mmoles) of methyl4- chlorobutyrate was added. The temperature fell and did not rise spontaneously. The mixture was stirred at l20--l30 for 30 minutes. (UV spectrum at 16 min. indicates the reaction was nearly, but not entirely, complete). The mixture wu cooled, the NaCl filtered and the filtrate was evaporated to an amber oil in vacuo (0.3 mm. bath 45). Meanwhile, 25 ml. of anhydrous methanol was cooled in an ice bath and anhydrous monomethylarnine was bubbled in until the volume was about 50 to 60 ml. and this solution was cooled to 15 and added to the amber oily ester prepared above and the resulting solution stirred magnetically at room temperature for 3 hours and allowed to stand at room temperature overnight. The solution was allowed to evaporate in a shallow dish giving moist crystals which after being slurried in 25 ml. of ethanol, filtered, washed with 2 times 5 ml. of ethanol and dried, melted at l19.5l2l. Recrystallized from 70 ml. of boiling absolute ethanol (charcoal), the product was obtained as needles melting at l25--126.

max.

Example 21 Preparation of N-methyl-Z-nitrol-irnidazolevaleramide To a stirred slurry of 5.10 g. of ground and sieved sublimed 2-nitroimidazole in 50 ml. of dimethylformamide (DMF) was added 10.0 ml. of 4.44 N CH ONa in CH OH to give a,pink solution. Addition of a pinch of azomycin gave a yellow solution which was heated to 150 and let cool to and with stirring, 10 ml. (about 12 g. or 62 mmoles) of methyl-5- bromovalerate was added. The temperature fell to 108 and then rose spontaneously to 114. The mixture was stirred at l l0-l 18 for 20 minutes. (UV spectrum of reaction mixture indicated complete reaction). The DMF was removed in vacuo finally heating at 75 (bath) 0.5 mm. to remove excess ester. The remaining oil was shaken with 50 ml. of CC], and

the NaBr was filtered and sucked dry. The filtrate pluswash' was evaporated in vacuo at 60, 0.5 mm. to give an amber oil.

Meanwhile 25 ml. of absolute methanol was cooled in an ice bath and anhydrous monomethylamine was bubbled in until the volume was about 50 ml. and this solution was added to the oily ester above. The resulting solution was stirred at room temperature for 5 hours, and was allowed to stand at room temperature overnight. The solution was allowed to evaporate in a shallow dish and the oil which formed was dissolved in absolute ethanol and the ethanol allowed to evaporate and this operation repeated to give a moist crystalline solid which after filtering, washing with 4 ml. of absolute ethanol and drying,

melted at 88-90. Recrystallized first from 20 ml. of absolute ethanol and then from 25 ml. of benzene plus 2 ml. of absolute ethanol, the product was obtained as heavy crystals melting at 94.596.5.

ELOH max.

313 my, e=7900 Example 22 Preparation of N-(2-aminoethyl)-2-nitro-l-imidazoleacetasolid melting at l36l38 (m.p. l44.5l45.5 another run). (The free base was unstable to storage and melted progressively lower on repeated recrystallization.) It was dissolved in 125 ml. of absolute ethanol and anhydrous HCl was bubbled into the solution for 30 minutes. The solid which formed was collected, washed with absolute ethanol, and dried at room temperature. Recrystallized twice from about 20 volumes of 95 percent ethanol, the product was obtained as a solid melting at l89190 (gas evolution).

Miiig 323 m e=7900 Example 23 Preparation of N-3,4-dimethoxyphenethyl-2-nitrol imidazoleacetamide A solution of 4.00 g. (21.7 mmoles) of 2-nitro-1- imidazoleacetic acid methyl ester plus 12 ml. of B-(3,4- dimethoxyphenyl)-ethylamine in 35 ml. of absolute methanol was stirred magnetically at room temperature for 1% hours by which time considerable solid had formed, and the slurry was allowed to stand at room temperature overnight. The slurry was cooled and the solid was filtered, washed with 25 ml. and then with ml. of absolute methanol and dried. Recrystallized from 350 ml. of boiling absolute ethanol, the product was obtained as colorless needles melting at l50.5151.

Example 24 Preparation of N-(2-nitrobenzyl)-2-nitro-1-imidazoleacetamide: MethodA To a partial solution of 14.00 g. (75.0 mmoles) of onitrobenzylamine hydrochloride in 120 ml. of methanol was added 15.1 ml. of 4.52 N Cl'l ONa in methanol. The precipitate of NaCl was filtered and to the filtrate was added 8.00 g. (43.2 mmoles) of 2-nitro-1-imidazoleacetic acid methyl ester which dissolved. The solution was allowed to stand at room temperature for 20 days. The mixture was refrigerated, and the crystals collected, m.p. l76l77. Recrystallized from 200 ml. of absolute ethanol, the product was obtained as crystals melting at l75.5176.5.

xii? 255, 312 my, e=7800, 8500.

Method B A solution of 3.11 g. (27.5 mmoles) of 2-nitroimidazole in 30 ml. of dimethylformamide (DMF) plus 6.09 ml. of 4.52 N CH ONa in methanol was heated to 152 and cooled to 110 and 6.35 g. (27.8 mmoles) of N-(o-nitrobenzyl)chloroacetamide was added and the mixture heated at 100120 for 30 minutes. The UV spectrum of reaction solution indicated that the reaction was complete. The mixture was concentrated at oil pump vacuum (bath 60) to a dark brown oil which was dissolved in 25 ml. of absolute ethanol and the solution allowed to stand at room temperature over the weekend to give brown crystals m.p. l64-l66. Recrystallized from ethanol (charcoal) the product was obtained as crystals melting at 166-168. A second recrystallization from ethanol gave crystals melting at 166.5-168.5. IR study demonstrated that the crystals melting at l66.5168.5 and those melting at 175.5-176.5 (Method A above) are polymorphic.

Example 25 Preparation of 2-nitro1-imidazoleacet-p-anisidide To a stirred slurry of 7.15 g. (63 mmoles) of ground and sieved sublimed 2-nitroimidazole in 100 ml. of dimethylformamide (DMF) was added 14.0 ml. (62 mmoles) of 4.44 N NaOCl-l in Cl-l Ol-l; the transient pink color went back to yellow. The mixture was heated to 151 and let cool to 115, and 12.8 g. (64 mmoles) of chloroacet-p-anisidide, m.p. 120- l2l.5 was added. The temperature fell to 100 and then rose spontaneously to 101 and the solution got hazy. The mixture was stirred at 115125 for 20 minutes, (UV spectrum indicates complete reaction), cooled and the salt filtered and the filtrate evaporated (0.5 mm., bath 48) to give a solid. The solid was ground in a mortar with about 75 ml. of absolute ethanol until a smooth paste resulted, and this was filtered and the solid washed with 3 times 25 ml. of absolute ethanol and dried. The dried product was powdered finely and recrystallized from 1250 ml. of boiling absolute ethanol (5 g. charcoal) to give flufi'y crystals melting at 207207.5.

250, 300 (shoulder), 314 m,., 6 18,200, 7200, 7700.

xi PrOH max.

Example 26 Preparation of N-tert-butyl-Z-nitro-l-imidazoleacetamide A solution of 7.00 g. (61.9 mmoles) of 2-nitroimidazole in 70 ml. of dimethylformamide (DMF) plus 13.7 ml. of 4.52 N NaOCl-l in Cl-l Ol-l was heated to 152 and cooled to 100 and 9.30 g. (62.1 mmoles) of N-tertbutylchloroacetamide was added. The mixture was stirred at 100 for 40 minutes,

313 mu, e=7100 EXAMPLE 27 Preparation of imidazoleacetamide A solution of 9.00 g. (48.6 mmoles) of 2-nitro-1- imidazoleacetic acid methyl ester plus 25 g. of p-methoxybenzylamine in 80 ml. of absolute methanol was stirred magnetically at room temperature. After 25 minutes there was a large amount of solid formed. The slurry was allowed to stand for an additional 2 hours at room temperature and was placed in the freezer for 1.5 hours. The solid was filtered, washed with 2 times 20 ml. of absolute methanol and dried, m.p. 2l02l3. Recrystallized from 1500 ml. of boiling absolute ethanol the product was obtained as fluffy needles melting at 21l-211.5.

N-(4-methoxybenzyl)-2-nitro-1- M552 275, 282, 312 mp; e=4600, 5200, 7800 EXAMPLE 28 Preparation of N-(2-methyl-4-arnino-5-pyrimidinylmethyl)-2- nitro-l-imidazoleacetamide A solution of 8.00 g. (43.2 mmoles) of 2-nitro-1-imidazole acetic acid methyl ester plus 17.84 g. (129 mmoles) of crude 2-methyl-4-a.rnino-5-methylamino-pyrimidine m.p. l24-127 in ml. of absolute methanol was stirred magnetically for 24 hours at room temperature during which time some solid formed. The mixture was allowed to stand at room temperature for an additional 5 days (total 6 days) and the solid was refrigerated overnight to give the product as colorless fine needles melting at 299-300 dec. (taken rapidly from 270).

53 235, 280, 315 mp; e=12,800; 8000; 7700 EXAMPLE 29 Preparation of 'N-(2-imidazolyl)-2-nitro-l-imidazoleacetamide A' mixture of 14.70 g. (111 mmoles) of finely powdered 2- aminoimidazole sulfate, 10.00 g. (54.0 mmoles) of 2-nitro-limidazoleacetic acid methyl ester, 250 ml. of absolute methanol, and 23.5 ml. of 4.44 N Cl-i oNa in methanol was stirred at room temperature for 3 days. The solid which was present was filtered, washed with absolute methanol and dried; the dry solid was slurried in 75 ml. of distilled water at room temperature, filtered, and washed with water. The moist insoluble solid was boiled with 175 ml. of distilled water (charcoal) and filtered hot. From the yellow filtrate after refrigeration overnight there was obtained fine yellow needles of the product having a melting point of 238239 dec. (from room temperature) or melting point of 24l242 dec. (rapidly from 200).

iPrOIl mni- EXAMPLE 30 solved and the initially yellow solution had become amber.

The hot solution was filtered and the filtrate was refrigerated for about 2 hours to yield a solid which upon recrystallizing from 300 ml. of boiling absolute ethanol (3.6 g. of Norit A) gave pale yellow needles of melting point l47l48.5.

iPrOH max.

315 m,., e=7l00 EXAMPLE 3l I Preparation of N-( 4-aminobenzyl)-2-nitro-l-imidazoleacetamide Two hundred milliliters of absolute ethanol was saturated with ammonia gas at and 30 g. (0.20 moles) of pnitrobenzo-nitrile was added and the mixture was hydrogenated using Raney Nickel catalyst and 1,200 lb.

hydrogen. Three moles of hydrogen was absorbed exothermically causing the temperature to rise to 61, and then the mixture was heated at 80-90 and 2 moles more of hydrogen was absorbed. The mixture was cooled, the catalyst removed, and

the light yellow filtrate was evaporated (water aspirator vacuum) to give a yellow oil the infrared spectrum of which was compatible with p-aminobenzylamine and which was used directly in the next step.

A- solution of 5.10 g. (27.5 mmoles) of 2-nitro-limidazoleacetic acid methyl ester and 10.0 ml. (10.9 g., density 1.09, 89.0 mmoles) of p-aminobenzylamine, prepared as above, in 50 ml. of absolute methanol was stirred at room temperature for 2 hours allowed to stand at room temperature for 16 hours and then refrigerated. The light amber colored needles which formed were collected, washed with ethanol, and dried to give a product melting at 204-207 dec. The product was finely powdered and recrystallized from 1,500 ml. of boiling ethanol (4 to 5 g. Norit A) to give needles melting at 208209. Recrystallized again from ethanol, the melting point was unchanged,

EXAMPLE 32 Preparation of N-isopropyl-3-( 2-nitro-l -imidazolyl)lactamide 2-Nitro-l-imidazole lactic acid ethyl ester (1.41 g., 6.15 mmoles) was slurried in 30 ml. of absolute methanol and with stirring 16 ml. of isopropyl amine was added whereupon the solid dissolved. The solution was stirred at room temperature for 17 hours. All insoluable solid was removed by filtration (IR spectrum indicates that it is an ester not an amide) and the filtrate was allowed to evaporate to give a gum plus a solid. Portions of absolute ethanol were added and allowed to evaporate until an amine odor was no longer noticeable, and the resulting sticky solid was slurried in 3 to 4 ml. of absolute ethanol, filtered and washed with 3 times 1 ml. of ethanol and dried. Recrystallized fi'om 20 ml. of boiling absolute ethanol the product was obtained a solid melting at l52.5-l 53.

max.

311 In e- 6500 Preparation of N,N-dimethyl-4-(2-nitro-l-imidazole)butyramide Method A To a slurry of 15.20 g. (134 mmoles) of sublimed 2-nitroimidazole in ml. of N,N-dimethylformamide was added 30.4 ml. of 4.44 N CH ONa in CH,OH. The solution turned pink and was made yellow by the addition of a pinch of 2- nitroirnidazole. The mixture was heated to 150 with stirring, was allowed to cool to 126 and 30 ml. of methyl-4-chlorobutyrate was added. The mixture was stirred at l20-l 30 for 30 min., cooled to 15, and the NaCl filtered and washed with dimethylformamide. The filtrate from the salt was evaporated to an amber oil in vacuo (0.8 min., bath 50) to give 4-(2- nitro-l-imidazole)butyric acid methyl ester which was used in the next step without further purification.

Absolute methanol (20 ml.) was cooled in an ice bath and anhydrous dimethylamine was bubbled in until the volume was nearly 50 ml. To this solution was added 3.0 ml. (3.9 g.) of 4-(2-nitro-l-imidazole)butyric acid methyl ester obtained as above and the solution was allowed to stand at room temperature for 69 hours. The solution was allowed to evaporate to an oil plus crystals. Portions of absolute ethanol were added and allowed to evaporate until the amine odorwas gone. The final slurry of crystals in about 5 ml. of ethanol was filtered and the crystals washed with 2 times 2 ml. of ethanol. The product was crystallized from 10 ml. of boiling absolute ethanol (0.1 g. Norit A) to give colorless crystals melting at 8889.

A222 314 my, e=7700 17 min. while maintaining the reaction temperature in the range 12" to --3. The reaction was stirred at 1 2 to 5 for 45 min., and the pH was adjusted to 6 with 8.5 ml. of glacial acetic acid. The solution was saturated with NaCl (about 55-60 g.) and the oil plus water was extracted with 450 ml. 5 and then with 250 ml. of cr-rcn. The Cl-lCl extracts were combined, dried over anhydrous MgSo the MgSo filtered, and the filtrate concentrated in vacuo (0.25 mm., bath 52) to a deep yellow oil. The N,N-dimethyl-4 chlorobutyramide thus obtained was used in the next step without further purifications.

To a slurry of 15.20 g (134 mmoles) of sublimed 2-nitroimidazole in 150 ml. of N,N-dimethylformamide was added 29.3 ml. of 4.56 N CH ONa in CH OH. The solution turned pink and was made yellow by the addition of a pinch of 2'- nitroimidazole. The solution was stirred and heated to 152 C. and allowed to cool to 131 C. whereupon 20.0 ml. (21.8 g. density 1.09, 146 mmoles) of N,N-dimethyl-4-chlorobutyramide prepared as above was added. The temperature fell to 121 and then rose spontaneously to 138, and a precipitate formed. The slurry was stirred at 120-125 for 30 min. and was then cooled to The NaCl was filtered and washed. The filtrate was evaporated in vacuo (0.25 mm., bath 54) to give a solid which was slurried while still warm in 35 ml. of ab solute ethanol which removed the color and the whole was refrigerated. The solid was filtered, washed with 2 times 15 ml. of ethanol and dried. Recrystallized from 200 ml. of boiling ethanol (3 g. Norit A) there was obtained pale yellow crystals melting at 8687.5 having an infrared spectrum in Cl-lCl: identical to that of the material prepared by Method A above.

EXAMPLE34 Preparation of n-isopropyl-4-( 2-nitro- 1 -irnidazole)butyrarnide A solution of 20.0 g. (0.500 moles) of NaOH in 200 ml. of distilled water was cooled to incipient freezing and 35 ml. (24 g. density 0.69, 0.41 moles) of isopropyl amine was added and the solution cooled to 10C. With stirring 52.5 g. (0.372 moles) of 4-chlorobutyryl chloride was added dropwise over a period of 17min. while maintaining the temperature in the range 10 to +l. A precipitate formed. The slurry was stirred briefly and the pH adjusted to 6 by the addition of 4.3 ml. of glacial acetic acid. The slurry was refrigerated and the solid was filtered, washed with 4 times 25 ml. of cold distilled water, and dried. The N-isopropyl-4-chlorobutyramide m.p. 52-54 thus obtained was used in the next step without further purification.

To a slurry of 10.1 g. (89.2 mmoles) of sublimed 2-nitroimidazole in 100 ml. of N,N-dimethylformamide was added 20.4 ml. of 4.34 N CH ONa in CH OH. The pink color turned back to yellow as the last of the 2-nitroimidazole dissolved. With stirring the solution was heated to 151C., allowed to cool to 121, and 16.0 g. (98.0 mmoles) of N-isopropyl-4- chlorobutyramide was added. The mixture was stirred at 120-130 for 30 min. (at which stage the ultraviolet absorption spectrum in 0.1N NaOH solution indicated no unreacted Z-nitroimidazole) and was then cooled to 20. The NaCl was filtered and washed with dimethylformamide. The filtrate was concentrated to an oil in vacuo (0.1 mm., bath 55). The oil crystallized on cooling. This solid was recrystallized from 30 ml. of warm absolute ethanol to give crystals melting at 99-103bL. Recrystallized from 40 ml. of hot ethanol (Norit A) there was obtained crystals melting at 103103.5. 65

EXAMPLE 35 Preparation of N,N-dimethyl-5-( Z-nitro- 1 imidazole )valeramide To a slurry of 15.00 g. (132.6 mmoles) of sublimed 2-nitroimidazole in 150 ml. of N,N-dimethylformamide was added 30.6 ml. of 4.34 N CPL-,ONa in CH Ol-l. The solution turned pink and was made yellow by the addition of a pinch of 2- nitroimidazole. The solution was stirred and heated to 152, and was allowed to cool to whereupon 30 g. (153 mmoles) of methyl-S-bromovalerate was added. The temperature fell to 102 and rose spontaneously to 1 10. The mixture was stirred at 100-l20 for 30 min. The mixture was evaporated to an oil in vacuo (0.5 mm., bath 75). The oil was shaken with 150 ml. of 1:1 (vol:vol) CHC1 :CCl and the NaBr was filtered and washed. The filtrate was again evaporated in vacuo (0.5 mm., bath 75) to a dark brown oil. This was distilled (in vacuo) to give a main fraction b.p. l58-159 at 0.1 mm. The distillate contained a small amount of 2-nitroimidazole which was removed by dissolving the distillate in Cl-lCl and extracting with aqueous Nal-lCO solution. The dried CHCl layer was evaporated to give 5-( 2-nitro-1- imidazole)valeric acid methyl ester as a yellow oil.

Absolute methanol (20 ml.) was cooled in an ice bath and anhydrous dimethylamine was bubbled in until the volume was nearly 50 ml. To this solution was added 5.0 g. (22 mmoles) of 5-(2-nitro-1-imidazole)valeric acid methyl ester and the solution was allowed to stand at room temperature for 11 days (until no appreciable amount of starting material remained as indicated by TLC). The solution was evaporated to give a solid which was recrystallized from 15 ml. of ethylacetate (Norit A) to give a solid melting at 8385. Recrystallized twice from 25 parts by volume of CCl there was obtained crystals melting at 85.5-87 C.

max.

EXAMPLE 36 Preparation of N,N-dimethyl-3-(2-nitro-1-imidazolyl)lactamide Absolute methanol (25 ml.) was cooled in an ice bath and anhydrous dimethylarnine was bubbled in until the volume of the solution was about 55 ml. Then 1.40 g. (61.1 mmoles) of 2-nitro-l-irnidazole lactic acid ethyl ester was added and swirled till dissolved. The solution was allowed to stand at room temperature for 17 hours and then allowed to evaporate to give a gum which was triturated with 5 ml. of 1:1 vol:vol, ethanolzbenzene. The solid which formed was filtered and washed with ethanol. Recrystallized from 20 ml. of boiling ethanol (Norit A) there was obtained pale yellow crystals melting at -131.5.

EXAMPLE 37 Preparation of N-benzyl-4-( 2-nitro- 1 -imidazole)butyramide A solution of 20.0 g. (0.500 moles) of NaOH in 200 m1. of

distilled water was cooled to freezing and 43 ml. (42 g., density 0.98, 0.392 moles) of benzylamine was added and the solution cooled to 10 and 48.0 g. (0.340 moles) of 4-chlorobutyryl chloride was added dropwise with stirring over a period of 14 min. maintaining the reaction temperature in the range 10 to 0. A white precipitate formed. The slurry was stirred in the cold for an additional. 5 min. and the pH was adjusted to 6 by the addition of 10.0 ml. of glacial acetic acid. The slurry was refrigerated briefly, and the solid was filtered, washed with 4 times 25 ml. of cold distilled water and dried. The N- benzyl-4-chlorobutyramide thus obtained melted at 66-67.5 and was used in the next step without further purification.

To a slurry of 10.1 g. (89.2 mmoles) of sublimed 2-nitroimidazole in 100 ml. of N,N-dimethylformamide was added 20.4 ml. of 4.34 N CH ONa in Cl-l Ol'l. The pink color turned back to yellow as the last of the 2-nitroimidazole dissolved. The solution was heated to 151 with stirring, allowed to cool to 130 and 20.0 g. (95 mmoles) of N-benzyl-4-chlorobutyramide was added. The mixture was stirred at l20-128 for 30 min., cooled to 20, and the NaCl was filtered and washed with dimethylformamide. The filtrate was evaporated to an amber oil in vacuo 0.1 mm., bath 55). The oil was dissolved in 100 ml. of ethanol and the solution was allowed to evaporate slowly in a shallow dish. The brown solid which formed was ground with 30 ml. of ethanol in a mortar, filtered, and washed with two times 10 ml. of ethanol (most of the color went into the ethanol) and dried. Again dissolved in 60 ml. of boiling ethanol with about 3 g. of Norit A added, the solution was boiled and filtered hot. The yellow filtrate was refrigerated to give a nearly colorless solid melting at 89.5-90.

REES 313 m,., e=7600 EXAMPLE 38 iPrOH max.

EXAMPLE 39 lreparation of N-isopropyl-6-( Z-nitro-l-imidazole)caproa-,

mide

- A mixture of 300 g. of o-bromocapronitrile plus 1,200 ml. of 48 percent aqueous HBr was refluxed for 10 hours. The mixture of aqueous phase, oil and solid was extracted with 3 times 2 l. of ether, the ether extracts combined, dried over Na,SO and evaporated to an oil. The oil was distilled to give (after a forerun) a main fraction b.p. l06127 (0.5-1.0 mm.), which crystallized. If desired this material could be recrystallized from an equal weight of petroleum ether to give crystals of 6-bromocaproic acid melting at 34-35.

Amixture of 40 g. of 6-bromocaproic acid plus 60 ml. of thionyl chloride was refluxed for one hour and the excess thionyl chloride was removed in vacuo (10 mm., bath 40) to leave-6-bromocaproyl chloride as a yellow oil which-was used in the next step without further purification.

A solution of 2.87 g. (7.13 mmoles) of NaOH in 27 ml. of distilled water was cooled to 10 C. and 5.25 ml. (3.64 g., density 0.694, 61.6 mmoles) of isopropyl amine was added and the solution cooled to 5. With stirring the 6-bromocaproyl chloride prepared as above from 10 g. of o-bromocaproic acid was added dropwise maintaining the reaction temperature between -5 and +5 whereupon a precipitate formed. The pH at the end of the reaction was 6. The slurry was refrigerated min. and the solid was filtered washed with distilled water and dried. The N-isopropyl-6-bromocaproamide was used in the next step without further purification.

Sublimed 2-nitroimidazole (2.82 g., 24.9 mmoles) was dissolved in 5.74mi. of 4.34 N CH ONa in Cl-l Ol'l. Addition of a pinch of Z-nitroirnidazole changed the color of the solution from pink to yellow. N,N-dimethylformamide (25 ml.) was added and the solution was heated to 152, cooled to 100, and 5.90 g. (25.1 mmoles) of N-isopropyl-6-bromocaproamide was added. The mixture was stirred at l00-1l0 for 30 min. The mixture was evaporated to an oil plus solids in vacuo (0.3 mm., bath 60). The residue was slurried in a mixture of acetone and Cl'lCl the NaBr filtered, and the filtrate evaporated in vacuo to an oil which crystallized. The solid was triturated with 10 ml. of distilled water, filtered and dried. The dried solid was dissolved in 50 ml. ofethyl acetate, slight amount insoluble material filtered off and the ethyl acetate removed. The resulting solid was recrystallized from 150 ml. of distilled water (1 g. Norit A) to give crystals melting at 87-88.

Am 314 111p, e=8000 EXAMPLE 40 Preparation of N-methyl-3-( 2-nitrol -imidazolyl )lactarnide Absolute methanol (25 ml.) was cooled in an ice bath and anhydrous monomethylamine was bubbled in until the total volume was about 60 ml. With stirring there was added 1.40 g. (61.1 mmoles) of 3-(2-nitro-l-imidazole) lactic acid ethyl ester which readily dissolved. The solution was stirred at room temperature for 19 hours and then allowed to evaporate. The oil which remained was dissolved in about 10 ml. of absolute ethanol and the ethanol allowed to evaporate. The solution process was repeated several times until a solid was obtained. This solid was slurried in 5 ml. of absolute ethanol, filtered,

washed with 2 ml. of ethanol, and dried. Recrystallization of the dry product once from 5 ml. of absolute ethanol and a second time from 4 ml. of ethanol gave chunky crystals melting at l29-l 32.

A222 312 my, e=4400 EXAMPLE 41 5. With stirring the 6-bromocaproyl chloride prepared from 7.27 g. (37.3 mmoles) of 6-bromocaproic acid (prepared as described hereinabove) was added dropwise maintaining the temperature between 5 and +5. A solid formed. The slurry was cooled for 15 min. and then the pH was adjusted to 6 with glacial acetic acid. Since the solid melted below room temperature, the mixture was extracted with 4 times 75 ml. of Cl-lCl The Cl-lCl extracts were combined, dried over anhydrous MgSO,, filtered, and evaporated to an oil in vacuo. The N-methyl-fi-bromocaproamide was used in the next step without further purification.

Sublimed Z-nitroimidazole (3.60 g., 31.8 mmoles) was dissolved in 7.34 ml. of 4.34 N CH ONa in cn,on. Thirty milliliters of N ,N-dimethylformamide was added, and the mixture was heated to 153, cooled to 1 10 and 7.93 g. (37.3 mmoles) of N-methyl-6bromocaproamide was added. The mixture was stirred at l00-l15 for 1 hour. The solution was concentrated to an oil plus solids in vacuo (0.3 mm., bath 60). Acetone (50 ml.) was added and the NaBr was filtered and the filtrate evaporated to an oil in vacuo (0.3 mm., bath 60). The oil was recrystallized from 30 ml. of boiling ethyl acetate 1 g. Norit A) to give the product as a solid, melting at 87.5-92.

The product was crystallized twice from 2 parts of boilingdistilled water to give crystals melting at -97.5. Recrystallized from 3 parts of absolute ethanol. there was obtained crystals melting at 9597.

iPrOH max.

To a solution of 3.6 g. of crude 4-(2-nit.ro-l-imidazole) butyric acid methyl ester (prepared as described hereinabove) in 20 ml. of absolute methanol was added 10 ml. of isobutylamine, and the solution was allowed to stand at room temperature for 17 days. Thin layer chromatography indicated no starting material was left. The solution was allowed to evaporate in a shallow dish to give oil plus crystals. To the oil and crystal mixture was added 20 ml. portions of ethanol which were allowed to evaporate slowly, until there was no more amine odor. The resulting solid was ground with 2-3 ml. of absolute ethanol in a mortar, filtered, washed with 1 ml. of ethanol, and dried. Recrystallized from 3 ml. of boiling absolute ethanol and cooled in a freezer, there was obtained crystals melting at 79.5-8 1 .5.

iPrOH max.

EXAMPLE 43 Preparation of N-isopropyl-S-(Z-nitro-1-imidazole)valerarnide A solution of 14.5 g. (0.362 moles) of NaOH in 160 ml. of distilled water was cooled to freezing and 25 ml. (17.2 g., density 0.690, 0.292 moles) of isopropylamine was added and the solution cooled to -12 C. With stirring 40.3 g. (0.260 moles) of -chloroveleryl chloride was added dropwise over a period of 17 minutes while maintaining the reaction temperature at -1 2 to 5. The mixture was stirred at 8 to 3 for an additional 30 minutes and the pH was adjusted to 6 with 6.7 ml. of glacial acetic acid. The solid which formed melted below room temperature so the mixture was extracted with 500 ml. and then with 2 times 100 ml. of CHCl The Cl'lCl extracts were combined, dried over anh. MgSO filtered, and the filtrate evaporated to a pale straw colored oil in vacuo 0.2 mm., bath 59). The N-isopropyl-5-chlorovaleramide thus obtained was used in the next step without further purification.

To a slurry of 15.2 g. (134 mmoles) of sublimed 2-nitroimidazole in 150 ml. of N,N-dimethylformamide was added 29.3 ml. of 4.56 N CH ONa in CH OH. The solid dissolved and the pink color was changed back to yellow by the addition of a pinch of 2-nitro-imidazole. With stirring the solution was heated to 152, was allowed to cool to 130, and 26.0 g. (25.0 ml., density 1.04, 146 mmoles) of N-isopropyl-S-chlorovalerarnide prepared as above was added. The mixture was stirred at l25136 for 30 minutes at which stage the U.V. spectrum in 0.1 N NaOH solution showed no trace of unreacted 2- nitroimidazole. The mixture was cooled to 13, and the NaCl was filtered and washed with dimethylformamide. The filtrate plus wash was evaporated to an oil in vacuo (0.15 mm., bath 58). The oil was dissolved in 35 ml. of absolute ethanol and the solution was allowed to evaporate in a shallow dish to give crystals. The crystals were ground in a mortar with m1. of absolute ethanol, filtered and washed with 3 to 4 ml. of ethanol, and dried. The dried product was dissolved in 45 ml. Cl-lCl and filtered from about 0.2 g. of insoluble material. The solution was allowed to evaporate and the solid was recrystallized from 22 ml. of absolute ethanol (cooled freezer) to give crystals melting at 8283. Recrystallized from 1:2 (vzv) cncmccn, the product was obtained as flufly colorless needles melting at 8383.5.

A212 313 my, e=8400 EXAMPLE 44 Preparation of N,N-dimethyl-6-(2-nitro-1-imidazole)caproamide A solution of 6.63 g. (0.166 mmoles) of NaOl-l in 22 ml. of distilled water was cooled to -5 and 37 g. of 25 percent solution of aqueous diemthylarnine (9.25 g., 0.205 moles dimethylarnine) was added and cooled to 0. With stirring the crude -bromocaproyl chloride prepared from 20 g. (102 mmoles) of 6-bromocaproic acid (prepared as described hereinabove) was added dropwise maintaining the temperature between 0 and 5. The mixture was then allowed to stand in the cold for an additional 15 minutes, the pH WAS AD- JUSTED TO 6 with glacial acetic acid, and 10 g. of NaCl was added. The mixture was extracted with 4 times 75 ml. of Cl-lCl the Cl-lCl extracts combined; dried over anh. MgSO filtered and concentrated to a yellow oil in vacuo (0.3 mm. bath 50). The N,N-dimethyl-6-bromocaproamide thus obtained was used in the next step without further purification.

To a solution of 10.0 g. (88.4 mmoles) of sublimed 2-nitroimidazole in 19.5 ml. of 4.56 N Cl-1 0Na in methanol was added enough solid 2-nitroimidazole to change the color-of the solution from pink to yellow. Dimethylformamide ml.) was added and the solution was heated to 152 and let cool to 100. Then 21.6 g. (96.4 mmoles) of N,N-dimethyl-6- bromocaproamide prepared as above was added. The mixture was heated'at 100-1 20 for 45 minutes. The U.V. spectrum in 0.1 N NaOl-l solution indicated absence of unreacted 2- nitroimidazole. The mixture was evaporated to an oil plus solid in vacuo (0.3 mm., bath 60). The residue was slurried in a mixture of Cl-lCl; plus acetone and the NaBr was filtered. The filtrate was evaporated in vacuo 0.3 mm., bath 60) to an oil which crystallized upon refrigerating overnight. This solid was recrystallized from 25 ml. of boiling absolute ethanol (2 g. Norit A) to give crystals melting at 73.575.5. Recrystallized from ethanol the product was obtained as crystals melting at 73.5-75.5

iPrOH max.

Preparation of N-benzyl-6-( 2-nitrol -imidazole )caproamide A solution of 5.80 g. (144 mmoles) of NaOH- in 50 ml. of distilled water was cooled to 0 and 12.10 g. (1 13 mmoles) of benzylamine was added and the solution cooled to 02 With vigorous stirring the 6-bromocaproyl chloride prepared from 20 g. (102 mmoles) of 6-bromocaproic acid (prepared as described hereinabove) was-added dropwise maintaining the temperature between 0 and 5. The mixture was cooled for an additional 15 minutes, and the solid was filtered, washed with distilled water and dried. The dried solid was recrystallized by dissolving in 100 ml. of ether and letting the solution evaporate to a small volume. There was thus obtained crystalline N-benzyl-6-bromocaproamide melting at 555 7.

To a slurry of 3.68 g. (32.6 mmoles) of sublimed 2- nitroimidazole in 35 ml. of N,N'dimethylformamide was added 7.16 ml. of 4.56 N CH ONa in CH OH. The solid dissolved to a pink solution which was made yellow by the addition of a pinch of 2-nitroimidazole. The solution was heated to 152, cooled to and 9.37 g. (33.0 moles) of recrystallized N-benzyl-6-bromocaproamide was added. The solution was heated at 100-1 15 for 30 minutes. The U.V. spectrum in 0.1N NaOl-l indicated that there was no unreacted 2- nitroimidazole. The mixture was evaporate in vacuo (0.3 mm., bath 60) to a yellow solid. This was slurried with 100 m1. of CHCl and the NaBr filtered. The filtrated was concentrated in vacuo to a yellow solid which was slurried with 35 ml. of absolute ethanol, cooled, filtered, washed with ethanol and dried to give a solid melting at 102- l03.5. Recrystallized from 17 ml. of boiling ethanol the product was obtained as crystals melting at l03-104.5.

EXAMPLE 46 layers were separated, and the ethyl acetate was extracted with 100 ml. of 1 N NaOl-l and then with 3 times 100 ml. of distilled water. The ethyl acetate was dried over anhydrous MgS filtered, and evaporated to an oil in vacuo (0.3 mm.,

bath 60). The oil crystallized on refrigerating to give the product melting at 4547. Recrystallized from 50 ml. of CCL (2 g. Norit A) the product was obtained as crystals melting at 47.5- 49.

M 22 313 my, e=7600 EXAMPLE 47 To a slurry of 100 g. (885 mmoles) of powdered sublimed 2- nitroimidazole in 500 ml. of N,N-dimethylformamide was added 200 ml. of-4.44 N NaOCl-l, in CH Ol-l. The solution became pink and just enough 2-nitroimidazole was added to give a yellow solution. The solution was heated to 153 in an open flask to remove methanol, cooled to 90 and 135 ml. (166 g., l .53- moles) of methylchloro acetate added. The temperature spontaneously roseto 122 and then fell with formation of a precipitate. The mixture was heated at l051 for 15 minutes and the solvent removed in vacuo (0.2 mm., bath 50) to give an oil. To the oil was added 500 ml. of reagent acetone. The product dissolved and salt which precipitated out was removed by filtration. The acetone solution was evaporated in vacuo to give a tan solid which was slurried in 200 ml. of ethanol, filtered, washed with 50 ml. of ethanol and dried. This dried solid was recrystallized from 350 ml. boiling ethanol (12 g. Norit A) to give pale yellow flakelets melting at EtOH inns.

EXAMPLE 48 centrated in vacuo to 600 ml. whereupon a solid formed. The

slurry was refrigerated overnight, and the off white solid was collected, washed with ethylacetate and dried to give the product as a solid melting at 159-l 60 (explodes, the decomposition point depends upon the rate of heating).

H12? 312 m e=7700 The material was partly destroyed upon recrystallization from boiling ethylacetate or boiling acetone giving an appreciably darker material having a melting point of 146 (explodes).

EXAMPLE 49 Preparation of N-[ 3-( 2-nitrol -imidazoly1)lactoyllpiperidine A mixture of 1.42 g. (6.2 mmoles) of 3-(2-nitro-1- imidazole) lactic acid ethyl ester in 22 ml. of piperidine was stirred until the solid dissolved (1.25 hr.). The solution was allowed to stand at room temperature for 75 hrs. and then the solution was allowed to evaporate in a shallow dish. The yellow gum which formed was dissolved in about 15 ml. of absolute ethanol, and the ethanol was allowed to evaporate. This process was repeated several times until a solid formed. The crystals were triturated with 4 ml. of absolute ethanol, filtered, washed with two times 1.5m]. of ethanol, dried and recrystallized from 10 ml. of boiling absolute ethanol to give fine colorless needles of N-[3-(2-nitro-l-imidazolyl)lactoyl]piperidine, m.p. 131-l32.

EXAMPLE 50 Preparation of N-isobutyl-3-(2-nitro-1-imidazolyl)lactamide To a mixture of 170 ml. of absolute methanol plus 100 ml. of isobutylarnine was added 8.04 g. of 3-(2-nitro-l-imidazole) lactic acid ethyl ester, and the mixture was stirred until the solid dissolved (about 15 min.) and the solution was allowed to stand at room temperature for about 22 hrs. The solution was then allowed to evaporate in a shallow dish to give a crystalline solid. The solid was slurried in absolute ethanol and the ethanol allowed to evaporate several times until the amine odor had largely disappeared. The ethanol moist solid was filtered, washed with 8 ml. of ethanol, dried and recrystallized from 50 ml. of boiling ethanol to give the product as pale yellowish needles, melting at l36-137,

EXAMPLE 51 Preparation of N-isopropyl-3-(2-nitro-l-imidazole)propionamide A solution of 13.4 g. (335 mmoles) of NaOH in 120 ml. of distilled water was cooled to 0 and 24.1 g. (410 mmoles) of isopropylamine was added. The solution was cooled to 0 and with vigorous stirring 26.0 g. (204 mmoles) of 3-chloropropionyl chloride was added dropwise maintaining the reaction temperature between 0 and 8. The mixture was kept for an additional 10 min. in the cooling bath, and the solid was filtered, washed with distilled water, dried and recrystallized from boiling distilled water to give N-isopropyl-3- chloropropionarnide, m.p. 69-70.5.

Sublimed 2-nitroimidazole (2.22 g., 19.6 mmoles) was dissolved in 4.3 ml. of 4.56 N Cl-l ONa in CH,OH. A pinch of 2- nitroimidazole was added, and the color of the solution changed from orangeto yellow. Twenty milliliters of N,N-

dimethyl-formarnide was added, the solution was heated to N-isopropyl-3-chloropropionamide prepared as above was added. The reaction mixture was stirred at ll0-130 for 4 hours. The mixture was evaporated to dryness in vacuo (0.3 mm, bath 60) and the residue was shaken vigorously with a mixture of 50 ml. of CHCl 20 ml. of saturated aqueous Na CO solution and 10 ml. of distilled water. The Cl-lCl, was

-with 2 ml. of ethanol to give an ofi-white solid which was recrystallized from 3 ml. of boiling absolute ethanol to give I crystals melting at 1 171 1 8.

EXAMPLE 5 2 Preparation of N-isopropyl-3-(2-nitro-l-imidazole)propionamide Sublimed Z-nitroimidazole (2.04 g., 18 mmoles) was dissolved in an equivalent amount of CH ONa in Cl-l OH, and the solution was evaporated to an oil which was triturated with toluene and the resulting solid was filtered, washed with ether and dried. This solid was stirred and refluxed with a solution of 2.69 g. (18 mmoles) of N-isopropyl-3-chloropropionamide in 40 ml. of toluene for 1 1 days. The solid (unreacted sodium salt of 2-nitroimidazole plus NaCl, 2.12 g.) was filtered;

About 20 percent of N-isopropyl-3-(2-nitro-l-imidazole) propionamide,

x:;;. 325 mp.

remained in the toluene.

EXAMPLE 5 3 Preparation of N-( 3-methoxypropyl)'-3-( 2-nitro- 1 imidazolyl)lactamide 3-( 2-Nitro-l-imidazole)lactic acid ethyl ester (1.42 g., 6.20 mmoles) was stirred at room temperature with a mixture of 28 ml. of absolute methanol plus7 ml. of 3-methoxypropylamine until the solid dissolved 1.5 hrs.). The solution was allowed to stand at room temperature for an additional 68 hrs., and then allowed to evaporate in a shallow dish to give crystals plus gum. The crystal and gum mixture was triturated with about 6 ml. of absolute ethanol (the gum solidified), filtered, washed with about 4 ml. of ethanol, dried and recrystallized from 10 ml. of boiling absolute ethanol to give N-(3-methoxypropyl)- 3-(2-Nitro-l-imidazolyl)lactamide, m.p. 1 1 11 12,

A222 312 my, e'=6100 EXAMPLE 54 Preparation of 2-nitro-l-imidazoleacetamide Sublimed 2-nitroimidazole (1.00 g., 8.85 mmoles) was dissolved in 8.7 ml. of l N aqueous sodium hydroxide solution. There was added 1.24 g. (13.3 mmoles) of chloroacetamide, and the mixture was refluxed for 1.5 hrs. The reaction mixture was allowed to cool to room temperature, and the crystals which formed were collected, slurried with 3 to 4 ml. of 1N sodium hydroxide solution, filtered, washed with 1 N sodium hydroxide and then with distilled water and dried. After recrystallizing twice from 5 ml. of boiling distilled water, there was obtained crystalline 2-nitro-l-imidazoleacetamide of melting point 182-183.5 having an IR spectrum identical to that of the material prepared by using dimethylformamide as solvent.

EXAMPLE 55 Preparation of N-methyl'-2-(4,5-dimethyl-2-nitro-limidazolyl)acetamide A solution of 2.39 g. (17.6 mmoles) of 4,5-dimethyl-2- nitroimidazole in 4 ml. of 4.44 N NaOCl-I in Cl-l OH was evaporated in vacuo to a solid which was dissolved in 25 ml. of dimethylformamide along with 2.38 g. (22.2 mmoles) of N- methylchloroacetamide. The solution was refluxed for 1 min. and the solvent removed in vacuo. The tacky solid was dissolved in 160 ml. of distilled water plus 17 ml. of 1N NaOl-l and the solution passed through a Dowex l-X4 (Acetate) column 2.4 X 20 cm., 100200 mesh and eluted with distilled water. This permitted separation of the product from the starting material. The fractions possessing ion-1.," MR 369 m,.

were evaporated to a tacky solid, dissolved twice in absolute ethanol and reconcentrated. The resulting material was extracted with ethylacetate and the ethylacetate evaporated. The resulting solid was recrystallized from 40 ml. of hot Cl-lCl to give crystals melting at l66-l69 and recrystallized a second time from 20 ml. of Cl-lCl to give the product as crystals melting at -1 72.

ml..." 368 m e=11,700

EXANIPLE 56 Preparation of 4,5-dibromo-2-nitroimidazole Ten grams (88.5 mmoles) of ground and sieved sublimed 2- nitIoimidazole was dissolved in 270 ml. of 1N NaOH solution; the solution was cooled in an ice bath, stirred magnetically, and 10.0 ml. (den. 2.93, 29.3 g., 184 mmoles) of bromine was added dropwise. The color of the bromine bleached gradually and a precipitate formed toward the end of the addition. The final solution bleached pl-l paper and was acid to litmus. Cooling and stirring were continued for 20 min. and the solid was filtered, washed with 3 times 10 ml. of distilled water, dried and recrystallized twice from 40 parts of boiling distilled water (charcoal) to give chunky yellow crystals of 4,5-dibromo-2- nitroimidazole, m.p. l36.5 137 dec.

EXAMPLE 57 Preparation of N-( p-FluorobenzyD-Z-Nitrol Imidazoleacetamide A solution of 5.00 g. of 2-nitro-1-imidazoleacetic acid methyl plus 10.0 g. of p-fluorobenzyl amine (Aldrich) in 50 ml. of methanol was allowed to sit at room temperature for 24 hours and was then refrigerated. The crystalline crude product, m.p. 190-192 C. was filtered. This was recrystallized from 180 ml. of boiling absolute ethanol to give crystalline product, m.p. 193194.

EXAMPLE 5 8 Preparation of N-( o-Fluorobenzyl)-2-Nitrol lmidazoleacetamide A mixture of 55 ml. of absolute methanol plus 7.50 g. of 2- nitro-l-imidazoleacetic acid methyl ester plus 15 g. of ofluorobenzylamine (Aldrich) was stirred at room temperature for 42 hours. The crude product was filtered, m.p. l901 9 1. Recrystallization from 275 ml. of boiling absolute ethanol gave needle crystals of the product, m.p. 190191.

EXAMPLE 59 Preparation of N-(m-Fluorobenzyl)-2-Nitrol lmidazoleacetamide A mixture of 55 ml. of absolute methanol 7.50 g. of 2-nitrolimidazoleacetic acid methyl ester, and 15 g. of mfluorobenzylamine (Aldrich) was stirred at room temperature for 43 hours. The crude product was filtered, m.p. l60162. This was recrystallized from ml. of boiling absolute ethanol to give the product, m.p. 162l 63.

We claim:

1. A compound of the formula wherein n is an integer from 2 to 6, R is lower alkyl and R is hydrogen or lower alkyl.

2. The compound according to claim 1 wherein the compound is N,N-dimethyl-4-( 2-nitrol imidazole )-butyramide.

3. The compound according to claim 1 wherein the compound is N,N-dimethyl-6-( 2-nitrol imidazole )-caproarnide.

4. The compound according t claim 1 wherein the compound is N-methyl-4( Z-nitro-l-irnidazole )-butyramide. 

2. The compound according to claim 1 wherein the compound is N, N-dimethyl-4-(2-nitro-1-imidazole)-butyramide.
 3. The compound according to claim 1 wherein the compound is N, N-dimethyl-6-(2-nitro-1-imidazole)-caproamide.
 4. The compound according t claim 1 wherein the compound is N-methyl-4-(2-nitro-1-imidazole)-butyramide.
 5. The compound according to claim 1 wherein said compound is N-methyl-5-(2-nitro-1-imidazole)- valeramide.
 6. N-(3-methoxypropyl)-2-nitro-1-imidazole acetamide.
 7. N-(2-aminoethyl)-2-nitro-1-imidazole acetamide.
 8. 2-nitro-1-imidazoleacet-p-anisidide.
 9. N-(p-fluorobenzyl)-2-nitro-1imidazole acetamide.
 10. N-(o-fluorobenzyl)-2-nitro-1-imidazole acetamIde.
 11. N-(m-fluorobenzyl)-2-nitro-1-imidazole acetamide.
 12. N-benzyl-4-(2-nitro-1-imidazole)-butyramide.
 13. N-(3,4-dimethoxyphenethyl)-2-nitro-1-imidazole acetamide.
 14. N-benzyl-2-nitro-1-imidazole acetamide.
 15. N-(o-chlorobenzyl)-2-nitro-1-imidazole acetamide.
 16. N-(o-nitrobenzyl)-2-nitro-1-imidazole acetamide. 